<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* p {
            color: red;
        }
        p.hello {
            font-weight: bolder;
        } */
    </style>
</head>
<body>
    <h1 id="first">我的第一个页面</h1>
    <div>
        <p style="color: aqua;">你好</p>
        <p class="hello">hello html</p>
    </div>
    <span class="hello">hello</span>
    <div class="content">

    </div>

    <a href="//baidu.com">百度</a>

    <button>点击</button>
    <script src="./dom.js"></script>
</body>
</html>